The present invention relates to an ultrasonic diagnosis device of the type in which the ultrasonic optical elements and the object at which the sound is directed are disposed in a liquid container and the image of the object is reproduced in one plane, the sound irradiation of the object takes place with incoherent sound radiation, and the device includes a condenser lens, an imaging objective and a detector system.
Conventional ultrasonic devices, for example, for medical diagnosis, operate according to the echo principle. In these devices, an electro-acoustic transducer head which, due to the piezoelectric ceramics contained therein, is able to transmit as well as receive, emits the shortest possible ultrasound pulse which is closely focussed in depth. Echoes are produced at body interfaces where acoustic impedance changes occur and these echoes are usually detected by the same acoustic head. The depth information is calculated from the travel time of the sound and scanning, which may be electronic or mechanical, produces a two-dimensional depth section image.
Ultrasonic diagnosis devices of the above-described type are disclosed, for example, in U.S. Pat. Nos. 3,913,061, 3,982,223 and 3,971,962.
These devices operate according to known imaging principles of the optical art, with ultrasonic or acoustic, lenses being used for the imaging. However, the design of these lenses requires that a special fluid, e.g. a fluorinated hydrocarbon, be enclosed between two polystyrene lenses, which results in high absorption losses in the special fluid and high reflection losses at the interfaces between the special fluid and the polystyrene. Moreover, within these imaging lenses, there are included prism systems which must be movably mounted in order to be able to deflect, or scan, the imaging beam. The generation of the incoherent acoustic field required for imaging is effected, for example, by means of 30 coherent individual ultrasound sources which are individually actuated and emit high intensity pulses. The detector device itself is composed of stationary detectors which must be arranged on a spherical surface.